(a) Field of the Invention
The present invention relates to a cooling system for a conversion device. More particularly, the present invention relates to a cooling system for a conversion device, for example an inverter system, which may be applied to a hybrid vehicle or an electric vehicle to cool components.
(b) Description of the Related Art
Recently, through the increasing interesting in green energy, hybrid vehicles, electric vehicles, fuel cell vehicles and so on have begun to replace the internal combustion engine vehicle. Most of these environmentally friendly vehicles include an electric motor that includes a permanent magnet. The electric motor is driven by phase current which is supplied by an inverter through a power cable. The phase current is converted from DC voltage into 3-phase AC voltage according to a PWM (Pulse Width Modulation) signal from a controller.
The inverter system includes a power module that includes an IGBT (Insulated Gate Bipolar Transistor), a capacitor module absorbing ripple current by switching of a switching element, an inductor driving a motor or filtering output voltage and so on. These constituent elements create heat when the inverter system is being operated. In particular, switching elements such as the power module produce an excessive amount of heat and other core components, such as an inductor, produce relatively little heat.
In the conventional art, a heat sink is usually applied to the aide in cooling these components. In this case, since the components are mounted to both upper and lower surfaces of the heat sink, the heat sink cools the components indirectly by coolant flowing through cooling lines.
However, in a conventional art, since the components vary in the amount of heat that is generated therein, are mounted to an upper and lower surface of the heat sink, and are cooled, the cooling efficiency of the components of the inverter system may be deteriorated.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.